
<?php


class Weixin_Lite{

  //接口API URL前缀
  const API_URL_PREFIX = 'https://api.mch.weixin.qq.com';
  //下单地址URL
  const UNIFIEDORDER_URL = "/pay/unifiedorder";
  //查询订单URL
  const ORDERQUERY_URL = "/pay/orderquery";
  //关闭订单URL
  const CLOSEORDER_URL = "/pay/closeorder";

  //公众账号ID
  private $appid;
  //商户号
  private $mch_id;
  //随机字符串
  private $nonce_str;
  //签名
  private $sign;
  //商品描述
  private $body;
  //商户订单号
  private $out_trade_no;
  //支付总金额
  private $total_fee;
  //终端IP
  private $spbill_create_ip;
  //支付结果回调通知地址
  private $notify_url;
  //交易类型
  private $trade_type;
  //支付密钥
  private $key;
  //证书路径
  private $SSLCERT_PATH;
  private $SSLKEY_PATH;
  //所有参数
  private $params = array();

  protected $config = array(

        // APPkey
        'appid' => '',
        'mchid' => '',
        'key'   =>'',
        'notify_url'=>'',
    );

 public function __construct() {
        if(DI()->config->get('app.Weixin'))
        $this->config = array_merge($this->config, DI()->config->get('app.Weixin'));
        $this->appid = isset($this->config['appid'])?$this->config['appid']:'';
        $this->mch_id = isset($this->config['mchid'])?$this->config['mchid']:'';
        $this->notify_url = isset($this->config['notify_url'])?$this->config['notify_url']:'';
        $this->key = isset($this->config['key'])?$this->config['key']:'';

    }
  
 
 /**
   * 下单方法
   * @param $params 下单参数
   */
  public function unifiedOrder( $params ){
    $this->body = $params['body'];
    $this->out_trade_no = $params['out_trade_no'];
    $this->total_fee = $params['total_fee'];
    $this->trade_type = $params['trade_type'];
    $this->nonce_str = $this->genRandomString();
    $this->spbill_create_ip = $_SERVER['REMOTE_ADDR'];
    $this->attach=$params['out_trade_no'];

    $this->params['appid'] = $this->appid;
    $this->params['mch_id'] = $this->mch_id;
    $this->params['nonce_str'] = $this->nonce_str;
    $this->params['body'] = $this->body;
    $this->params['out_trade_no'] = $this->out_trade_no;
    $this->params['total_fee'] = $this->total_fee;
    $this->params['spbill_create_ip'] = $this->spbill_create_ip;
    $this->params['trade_type'] = $this->trade_type;
    $this->params['notify_url'] = $this->notify_url;
    $this->params['attach']     =  $this->attach;
    //获取签名数据
    $this->sign = $this->MakeSign( $this->params);
    //print_r($this->sign);
    $this->params['sign'] = $this->sign;
    //print_r($this->params);
    $xml = $this->data_to_xml($this->params);
    //print_r($xml);
    $response = $this->postXmlCurl($xml, self::API_URL_PREFIX.self::UNIFIEDORDER_URL);
    //print_r($response);
    if( !$response ){
      return false;
    }
    $result = $this->xml_to_data( $response );

    if( !empty($result['result_code']) && !empty($result['err_code']) ){
      $result['err_msg'] = $this->error_code( $result['err_code'] );
       
    }
     return $result;
  }
  
  /**
   * 查询订单信息
   * @param $out_trade_no   订单号
   * @return array
   */
  public function orderQuery( $out_trade_no ){
    
    $this->params['appid'] = $this->appid;
    $this->params['mch_id'] = $this->mch_id;
    $this->params['nonce_str'] = $this->genRandomString();
    $this->params['out_trade_no'] = $out_trade_no;
    
    //获取签名数据
    $this->sign = $this->MakeSign( $this->params );
    $this->params['sign'] = $this->sign;
    $xml = $this->data_to_xml($this->params);
    $response = $this->postXmlCurl($xml, self::API_URL_PREFIX.self::ORDERQUERY_URL);
    if( !$response ){
      return false;
    }
    $result = $this->xml_to_data( $response );
    if( !empty($result['result_code']) && !empty($result['err_code']) ){
      $result['err_msg'] = $this->error_code( $result['err_code'] );
    } 
    return $result;
  }
  
  /**
   * 关闭订单
   * @param $out_trade_no   订单号
   * @return array
   */
  public function closeOrder( $out_trade_no ){
    $this->params['appid'] = $this->appid;
    $this->params['mch_id'] = $this->mch_id;
    $this->params['nonce_str'] = $this->genRandomString();
    $this->params['out_trade_no'] = $out_trade_no;
    
    //获取签名数据
    $this->sign = $this->MakeSign( $this->params );
    $this->params['sign'] = $this->sign;
    $xml = $this->data_to_xml($this->params);
    $response = $this->postXmlCurl($xml, self::API_URL_PREFIX.self::CLOSEORDER_URL);
    if( !$response ){
      return false;
    }
    $result = $this->xml_to_data( $response );
    return $result;
  }
  
  /**
   * 
   * 获取支付结果通知数据
   * return array
   */
  public function getNotifyData(){
    //获取通知的数据
    $xml = $GLOBALS['HTTP_RAW_POST_DATA'];
    $data = array();
    if( empty($xml) ){
      return false;
    }
    $data = $this->xml_to_data( $xml );
    if( !empty($data['return_code']) ){
      if( $data['return_code'] == 'FAIL' ){
        return false;
      }
    }
    return $data;
  }
  
  /**
   * 接收通知成功后应答输出XML数据
   * @param string $xml
   */
  public function replyNotify(){
    $data['return_code'] = 'SUCCESS';
    $data['return_msg'] = 'OK';
    $xml = $this->data_to_xml( $data );
    echo $xml;
    die();
  }
  
   /**
    * 生成APP端支付参数
    * @param  $prepayid 预支付id
    */
   public function getAppPayParams( $prepayid ){
     $data['appid'] = $this->appid;
     $data['partnerid'] = $this->mch_id;
     $data['prepayid'] = $prepayid;
     $data['package'] = 'Sign=WXPay';
     $data['noncestr'] = $this->genRandomString();
     $data['timestamp'] = time();
     $data['sign'] = $this->MakeSign( $data ); 
     return $data;
   }
  
  
  /**
   * 生成签名
   *  @return 签名
   */
  public function MakeSign( $params ){
    //签名步骤一：按字典序排序数组参数
    ksort($params);
    $string = $this->ToUrlParams($params);
    //签名步骤二：在string后加入KEY
    $string = $string . "&key=".$this->key;
    //print_r($string);
    //签名步骤三：MD5加密
    $string = md5($string);
    //签名步骤四：所有字符转为大写
    $result = strtoupper($string);
    
    return $result;

  }
  
  /**
   * 将参数拼接为url: key=value&key=value
   * @param $params
   * @return  string
   */
  public function ToUrlParams( $params ){
    $string = '';
    if( !empty($params) ){
      $array = array();
      foreach( $params as $key => $value ){
        $array[] = $key.'='.$value;
      }
      $string = implode("&",$array);
    }
    return $string;
  }
  
  /**
   * 输出xml字符
   * @param $params   参数名称
   * return string    返回组装的xml
   **/
  public function data_to_xml( $params ){
    if(!is_array($params)|| count($params) <= 0)
    {
        return false;
      }
      $xml = "<xml>";
      foreach ($params as $key=>$val)
      {
        if (is_numeric($val)){
          $xml.="<".$key.">".$val."</".$key.">";
        }else{
          $xml.="<".$key."><![CDATA[".$val."]]></".$key.">";
        }
        }
        $xml.="</xml>";
        return $xml; 
  }
  

  /**
     * 将xml转为array
     * @param string $xml
   * return array
     */
  public function xml_to_data($xml){  
    if(!$xml){
      return false;
    }
        //将XML转为array
        //禁止引用外部xml实体
        libxml_disable_entity_loader(true);
        $data = json_decode(json_encode(simplexml_load_string($xml, 'SimpleXMLElement', LIBXML_NOCDATA)), true);    
    return $data;
  }
  
  
  /**
   * 获取毫秒级别的时间戳
   */
  private static function getMillisecond(){
    //获取毫秒的时间戳
    $time = explode ( " ", microtime () );
    $time = $time[1] . ($time[0] * 1000);
    $time2 = explode( ".", $time );
    $time = $time2[0];
    return $time;
  }
  
  /**
   * 产生一个指定长度的随机字符串,并返回给用户 
   * @param type $len 产生字符串的长度
   * @return string 随机字符串
   */
  private function genRandomString($len = 32) {
    $chars = array(
      "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k",
      "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v",
      "w", "x", "y", "z", "A", "B", "C", "D", "E", "F", "G",
      "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R",
      "S", "T", "U", "V", "W", "X", "Y", "Z", "0", "1", "2",
      "3", "4", "5", "6", "7", "8", "9"
    );
    $charsLen = count($chars) - 1;
    // 将数组打乱 
    shuffle($chars);
    $output = "";
    for ($i = 0; $i < $len; $i++) {
      $output .= $chars[mt_rand(0, $charsLen)];
    }
    return $output;
  }
  
  /**
   * 以post方式提交xml到对应的接口url
   * 
   * @param string $xml  需要post的xml数据
   * @param string $url  url
   * @param bool $useCert 是否需要证书，默认不需要
   * @param int $second   url执行超时时间，默认30s
   * @throws WxPayException
   */
  private function postXmlCurl($xml, $url, $useCert = false, $second = 30){   
    $ch = curl_init();
    //设置超时
    curl_setopt($ch, CURLOPT_TIMEOUT, $second);
    
    curl_setopt($ch,CURLOPT_URL, $url);
    curl_setopt($ch,CURLOPT_SSL_VERIFYPEER,FALSE);
    curl_setopt($ch,CURLOPT_SSL_VERIFYHOST,2);
    //设置header
    curl_setopt($ch, CURLOPT_HEADER, FALSE);
    //要求结果为字符串且输出到屏幕上
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);
  
    if($useCert == true){
      //设置证书
      //使用证书：cert 与 key 分别属于两个.pem文件
      curl_setopt($ch,CURLOPT_SSLCERTTYPE,'PEM');
      //curl_setopt($ch,CURLOPT_SSLCERT, WxPayConfig::SSLCERT_PATH);
      curl_setopt($ch,CURLOPT_SSLKEYTYPE,'PEM');
      //curl_setopt($ch,CURLOPT_SSLKEY, WxPayConfig::SSLKEY_PATH);
    }
    //post提交方式
    curl_setopt($ch, CURLOPT_POST, TRUE);
    curl_setopt($ch, CURLOPT_POSTFIELDS, $xml);
    //运行curl
    $data = curl_exec($ch);
    //返回结果
    
    if($data){
      curl_close($ch);
      return $data;
    } else { 
      $error = curl_errno($ch);
      curl_close($ch);
      return false;
    }
  }
  
  /**
    * 错误代码
    * @param  $code   服务器输出的错误代码
    * return string
    */
   public function error_code( $code ){
     $errList = array(
      'NOAUTH'        =>  '商户未开通此接口权限',
      'NOTENOUGH'       =>  '用户帐号余额不足',
      'ORDERNOTEXIST'     =>  '订单号不存在',
      'ORDERPAID'       =>  '商户订单已支付，无需重复操作',
      'ORDERCLOSED'     =>  '当前订单已关闭，无法支付',
      'SYSTEMERROR'     =>  '系统错误!系统超时',
      'APPID_NOT_EXIST'   =>  '参数中缺少APPID',
      'MCHID_NOT_EXIST'   =>  '参数中缺少MCHID',
      'APPID_MCHID_NOT_MATCH' =>  'appid和mch_id不匹配',
      'LACK_PARAMS'     =>  '缺少必要的请求参数',
      'OUT_TRADE_NO_USED'   =>  '同一笔交易不能多次提交',
      'SIGNERROR'       =>  '参数签名结果不正确',
      'XML_FORMAT_ERROR'    =>  'XML格式错误',
      'REQUIRE_POST_METHOD' =>  '未使用post传递参数 ',
      'POST_DATA_EMPTY'   =>  'post数据不能为空',
      'NOT_UTF8'        =>  '未使用指定编码格式',
     ); 
     if( array_key_exists( $code , $errList ) ){
      return $errList[$code];
     }
   }



}